Manufacturing method of optical fiber preform

摘要

A method for manufacturing an optical fiber preform that can produce an optical fiber having desired characteristics over the longer length thereof. A crude preform provided with a core region and a cladding region is prepared (Step S1), and at a plurality of positions in the longitudinal direction of the crude preform, a refractive index profile in the cross-section of the crude preform is measured (Step S2). Then, the shape of the cladding region is demarcated based on the shape of the profile (Step S3). Subsequently, the crude preform is ground based on the results of the demarcation (Step S4). Thus, an optical fiber preform that enables the manufacture of an optical fiber having target characteristics is manufactured.